4 ms·

More and more small pools are closing their doors due to the influx of ASICs. It's sad to see, and a big worry for the future security of the blockchain.

pygy_ 14y ago
Wait until ASICS become widespread, and pools are once again needed.
brador 14y ago
What is ASICs? Google is giving me tennis shoes.
- codesuela 14y ago
  It's basically a computer with specialized hardware whose sole purpose is to mine Bitcoins, see http://www.butterflylabs.com/ http://www.butterflylabs.com/ for an example
- mfenniak 14y ago
  An ASIC is an application-specific integrated circuit. Basically, dedicated hardware like this: http://www.butterflylabs.com/ http://www.butterflylabs.com/
- phormula 14y ago
  Application Specific Integrated Circuit in the bitcoin context they chips created for the specific purpose of hashing, allowing you to mine for bitcoins quickly and effficiently.
- litecoinguru 14y ago
  Here's an explanation: http://cryptojunky.com/blog/2013/02/17/bitcoin-asic-roundup/ http://cryptojunky.com/blog/2013/02/17/bitcoin-asic-roundup/
- mheathr 14y ago
  ASIC is an implementation of a circuit. They will be the fastest implementation of the logic, however they are the most expensive implementation of that logic by far. Unlike FPGAs once logic is implemented in an ASIC the implementation is set in stone, so if there is a bug in the hardware fixing it will require producing an additional run and incur the expensive cost again. The high cost is why FPGAs are popular for both prototyping and production units when possible as it is much cheaper for smaller quantities. ASIC having exactly the logic necessary to target a task is why they are the most efficient at the task compared to general purpose hardware. https://en.wikipedia.org/wiki/Application-specific_integrated_circuit https://en.wikipedia.org/wiki/Application-specific_integrate...
sp332 14y ago
BTCguild got the lion's share of ASIC miners (so far, anyway). There's actually been some worry since that pool is approaching 51% of the network's power! That means with a malicious server, the admins could (theoretically, not saying they would) take over the entire network. They have taken some steps to reduce the number of miners in the guild, and have pledged to raise their fees if their control goes over 40%, to force miners to other pools. https://bitcointalk.org/index.php?topic=168108.0 https://bitcointalk.org/index.php?topic=168108.0 (The way they could take over the network is by crafting a new blockchain, forging fake transactions or even claiming that they own all bitcoins. If they solve blocks faster than the rest of the network, soon their malicious chain would become longer and therefore accepted by all clients! Clients always trust the longest chain because it takes the most work to make, so you would have to control most of the mining power to fake anything for long.)
- michaelbuckbee 14y ago
  So say they did all of the malicious things you've stated, is that illegal?
  - apalmer 14y ago
    Legality is an interesting question. I would guess it would not be illegal to manipulate the bitcoin protocol for personal gains, however any fraud committed would probably be illegal on its own merits.
  - sneak 14y ago
    Illegal in which of the ~200 countries that Bitcoin is currently being used in?
- lgeek 14y ago
  > The way they could take over the network is by crafting a new blockchain, forging fake transactions or even claiming that they own all bitcoins. If they solve blocks faster than the rest of the network, soon their malicious chain would become longer and therefore accepted by all clients! Clients always trust the longest chain because it takes the most work to make, so you would have to control most of the mining power to fake anything for long. This is incorrect. Having 51% or more of the computing power of the network doesn't allow you to replace the whole blockchain (there are checkpoints, and it gets more difficult as you want to replace a bigger part of it). You also can't forge new transactions, since transactions need to be signed by the sender. Basically the only practical attack (assuming no serious bugs in the clients) is a double spend: they could pay out of their own wallet a sum X to a third party, the third party checks that the transaction has Y confirmations (remember, as Y grows, it gets more difficult to pull this off), they receive whatever they've bough from the third party, and then they start pushing a different and longer block not including the transaction.
betterunix 14y ago
If only there were a formal definition of "security" that we could work with...

pygy_ 14y ago

Wait until ASICS become widespread, and pools are once again needed.

brador 14y ago

What is ASICs? Google is giving me tennis shoes.

codesuela 14y ago
It's basically a computer with specialized hardware whose sole purpose is to mine Bitcoins, see http://www.butterflylabs.com/ http://www.butterflylabs.com/ for an example
mfenniak 14y ago
An ASIC is an application-specific integrated circuit. Basically, dedicated hardware like this: http://www.butterflylabs.com/ http://www.butterflylabs.com/
phormula 14y ago
Application Specific Integrated Circuit in the bitcoin context they chips created for the specific purpose of hashing, allowing you to mine for bitcoins quickly and effficiently.
litecoinguru 14y ago
Here's an explanation: http://cryptojunky.com/blog/2013/02/17/bitcoin-asic-roundup/ http://cryptojunky.com/blog/2013/02/17/bitcoin-asic-roundup/
mheathr 14y ago
ASIC is an implementation of a circuit. They will be the fastest implementation of the logic, however they are the most expensive implementation of that logic by far. Unlike FPGAs once logic is implemented in an ASIC the implementation is set in stone, so if there is a bug in the hardware fixing it will require producing an additional run and incur the expensive cost again. The high cost is why FPGAs are popular for both prototyping and production units when possible as it is much cheaper for smaller quantities. ASIC having exactly the logic necessary to target a task is why they are the most efficient at the task compared to general purpose hardware. https://en.wikipedia.org/wiki/Application-specific_integrated_circuit https://en.wikipedia.org/wiki/Application-specific_integrate...

sp332 14y ago

BTCguild got the lion's share of ASIC miners (so far, anyway). There's actually been some worry since that pool is approaching 51% of the network's power! That means with a malicious server, the admins could (theoretically, not saying they would) take over the entire network. They have taken some steps to reduce the number of miners in the guild, and have pledged to raise their fees if their control goes over 40%, to force miners to other pools. https://bitcointalk.org/index.php?topic=168108.0 https://bitcointalk.org/index.php?topic=168108.0 (The way they could take over the network is by crafting a new blockchain, forging fake transactions or even claiming that they own all bitcoins. If they solve blocks faster than the rest of the network, soon their malicious chain would become longer and therefore accepted by all clients! Clients always trust the longest chain because it takes the most work to make, so you would have to control most of the mining power to fake anything for long.)

michaelbuckbee 14y ago
So say they did all of the malicious things you've stated, is that illegal?
- apalmer 14y ago
  Legality is an interesting question. I would guess it would not be illegal to manipulate the bitcoin protocol for personal gains, however any fraud committed would probably be illegal on its own merits.
- sneak 14y ago
  Illegal in which of the ~200 countries that Bitcoin is currently being used in?
lgeek 14y ago
> The way they could take over the network is by crafting a new blockchain, forging fake transactions or even claiming that they own all bitcoins. If they solve blocks faster than the rest of the network, soon their malicious chain would become longer and therefore accepted by all clients! Clients always trust the longest chain because it takes the most work to make, so you would have to control most of the mining power to fake anything for long. This is incorrect. Having 51% or more of the computing power of the network doesn't allow you to replace the whole blockchain (there are checkpoints, and it gets more difficult as you want to replace a bigger part of it). You also can't forge new transactions, since transactions need to be signed by the sender. Basically the only practical attack (assuming no serious bugs in the clients) is a double spend: they could pay out of their own wallet a sum X to a third party, the third party checks that the transaction has Y confirmations (remember, as Y grows, it gets more difficult to pull this off), they receive whatever they've bough from the third party, and then they start pushing a different and longer block not including the transaction.

betterunix 14y ago

If only there were a formal definition of "security" that we could work with...